Weather forecast for April 5

April 5, 2011

The 1,024 millibar high over California responsible for yesterday’s beautiful weather will weaken and move eastward today.

A dry cold front will sweep southeastward over the Central Coast later today with cooler temperatures and coastal low clouds and fog tonight into Wednesday.

The main effect of this cold front will be to produce moderate gale to fresh gale (32 to 46-mph) northwesterly winds Wednesday.

The northwesterly winds will decrease to strong to gale force (25 to 31-mph) levels on Thursday, further decreasing on Friday and Saturday

An upper-level low may produce a few rain showers late Thursday night into Friday. Temperatures will continue to trend downward on Thursday with maximum temperatures struggling to get out of the 50s on Thursday and again on Friday with overnight minimums in the 30s and 40s with frost possible in the inland valleys on Friday and again on Saturday morning as this low will produce much below normal temperatures for early April into next weekend.

The upper-level low moves out of the region over the weekend for fair and warmer weather, but temperatures will remain below normal and cool into next week.

This afternoon’s strong to gale force (25 to-38 mph) northwesterly winds will generate 4- to 6-foot northwesterly (300-degree deep-water) sea and swell with a 4- to 11-second period this afternoon through tonight.

These winds will further increase to moderate gale to fresh gale (32 to 46-mph) levels later on Wednesday. These winds combined with a Gulf of Alaska swell will produce a 7- to
9-foot northwesterly (310-degree deep-water) sea and swell (with a 7- to 17-second period) on Wednesday morning, building to 10- to 12-feet (with a 7- to 16-second period) Wednesday afternoon and night.

The northwesterly winds will decrease to strong to gale force (25 to 31-mph) levels on Thursday and consequently the northwesterly (300-degree deep-water) sea and swell will decrease to 8- to 10-foot level (with a 7- to 13-second period) during this timeframe.

Arriving from the Southern Hemisphere:

A 1- to 2-foot Southern Hemisphere (225-degree deep-water) swell (with a 20- to 22-second period) will arrive along the coast Wednesday, increasing to 2 to 4 feet (with an 18- to 20-second period) Thursday through Friday.

* Note: Height (significant swell height) is the average height of the waves in the top third of the wave record. Maximum wave height may be up to TWICE the height in the data shown in the above table.

1945 – The temperature at Eagles Nest, NM, plunged to 45 degrees below zero to establish an April record for the United States. (Sandra and TI Richard Sanders – 1987)

1989 – Unseasonably hot weather prevailed in the southwestern U.S. Afternoon highs of 100 degrees at Santa Maria CA and 105 degrees in Downtown Los Angeles established records for the month of April. (The National Weather Summary)

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